Abstract
Many repeating units of Drosophila melanogaster rDNA contain a DNA sequence within the gene for 28S rRNA that does not code for rRNA. This sequence has been called the ribosomal insertion [Wellauer, P. K. & Dawid, I. B. (1977) Cell 10, 193-212]. We report here that members of the same sequence family occur outside the ribosomal locus. “Non-rDNA insertion DNA” was separated from rDNA by density gradient centrifugation, and sequences homologous to the ribosomal insertion were detected by hybridization with restriction endonuclease fragments derived from a cloned rDNA repeating unit. Pure insertion sequences from cloned rDNA separated from main band DNA and behaved like a component with high G + C content. Non-rDNA components hybridizing to the insertion also separated from main band DNA but less so than pure insertion sequences, suggesting that non-rDNA insertion sequences are linked to DNA of different nucleotide composition. Restriction endonuclease analysis of non-rDNA insertion DNA showed many fragments of different sizes. The patterns obtained were similar in embryonic, larval, pupal, and adult DNA and DNA from cultured cells (Schneider cell line 3). Non-rDNA insertion sequences account for about 0.2% of the genome or about 400 kbases of DNA per haploid complement.
Keywords: ribosomal DNA, rRNA, Drosophila melanogaster, density gradient centrifugation, repetitive sequence families
Full text
PDFImages in this article
Selected References
These references are in PubMed. This may not be the complete list of references from this article.
- Botchan P., Reeder R. H., Dawid I. B. Restriction analysis of the nontranscribed spacers of Xenopus laevis ribosomal DNA. Cell. 1977 Jul;11(3):599–607. doi: 10.1016/0092-8674(77)90077-0. [DOI] [PubMed] [Google Scholar]
- Cohen S. N. Transposable genetic elements and plasmid evolution. Nature. 1976 Oct 28;263(5580):731–738. doi: 10.1038/263731a0. [DOI] [PubMed] [Google Scholar]
- Dawid I. B. DNA-DNA hybridization on membrane filters: a convenient method using formamide. Biochim Biophys Acta. 1977 Jul 15;477(2):191–194. doi: 10.1016/0005-2787(77)90235-0. [DOI] [PubMed] [Google Scholar]
- Glover D. M., Hogness D. S. A novel arrangement of the 18S and 28S sequences in a repeating unit of Drosophila melanogaster rDNA. Cell. 1977 Feb;10(2):167–176. doi: 10.1016/0092-8674(77)90212-4. [DOI] [PubMed] [Google Scholar]
- Grunstein M., Hogness D. S. Colony hybridization: a method for the isolation of cloned DNAs that contain a specific gene. Proc Natl Acad Sci U S A. 1975 Oct;72(10):3961–3965. doi: 10.1073/pnas.72.10.3961. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Klukas C. K., Dawid I. B. Characterization and mapping of mitochondrial ribosomal RNA and mitochondrial DNA in Drosophila melanogaster. Cell. 1976 Dec;9(4 Pt 1):615–625. doi: 10.1016/0092-8674(76)90044-1. [DOI] [PubMed] [Google Scholar]
- Maniatis T., Jeffrey A., Kleid D. G. Nucleotide sequence of the rightward operator of phage lambda. Proc Natl Acad Sci U S A. 1975 Mar;72(3):1184–1188. doi: 10.1073/pnas.72.3.1184. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Manuelidis L. A simplified method for preparation of mouse satellite DNA. Anal Biochem. 1977 Apr;78(2):561–568. doi: 10.1016/0003-2697(77)90118-x. [DOI] [PubMed] [Google Scholar]
- Morrow J. F., Cohen S. N., Chang A. C., Boyer H. W., Goodman H. M., Helling R. B. Replication and transcription of eukaryotic DNA in Escherichia coli. Proc Natl Acad Sci U S A. 1974 May;71(5):1743–1747. doi: 10.1073/pnas.71.5.1743. [DOI] [PMC free article] [PubMed] [Google Scholar]
- Pellegrini M., Manning J., Davidson N. Sequence arrangement of the rDNA of Drosophila melanogaster. Cell. 1977 Feb;10(2):213–214. doi: 10.1016/0092-8674(77)90215-x. [DOI] [PubMed] [Google Scholar]
- Southern E. M. Detection of specific sequences among DNA fragments separated by gel electrophoresis. J Mol Biol. 1975 Nov 5;98(3):503–517. doi: 10.1016/s0022-2836(75)80083-0. [DOI] [PubMed] [Google Scholar]
- Starlinger P., Saedler H. IS-elements in microorganisms. Curr Top Microbiol Immunol. 1976;75:111–152. doi: 10.1007/978-3-642-66530-1_4. [DOI] [PubMed] [Google Scholar]
- Tartof K. D., Dawid I. G. Similarities and differences in the structure of X and Y chromosome rRNA genes of Drosophila. Nature. 1976 Sep 2;263(5572):27–30. doi: 10.1038/263027a0. [DOI] [PubMed] [Google Scholar]
- Wellauer P. K., Dawid I. B., Brown D. D., Reeder R. H. The molecular basis for length heterogeneity in ribosomal DNA from Xenopus laevis. J Mol Biol. 1976 Aug 25;105(4):461–486. doi: 10.1016/0022-2836(76)90229-1. [DOI] [PubMed] [Google Scholar]
- Wellauer P. K., Dawid I. B. The structural organization of ribosomal DNA in Drosophila melanogaster. Cell. 1977 Feb;10(2):193–212. doi: 10.1016/0092-8674(77)90214-8. [DOI] [PubMed] [Google Scholar]
- Wellauer P. K., Reeder R. H., Carroll D., Brown D. D., Deutch A., Higashinakagawa T., Dawid I. B. Amplified ribosomal DNA from Xenopus laevis has heterogeneous spacer lengths. Proc Natl Acad Sci U S A. 1974 Jul;71(7):2823–2827. doi: 10.1073/pnas.71.7.2823. [DOI] [PMC free article] [PubMed] [Google Scholar]
- White R. L., Hogness D. S. R loop mapping of the 18S and 28S sequences in the long and short repeating units of Drosophila melanogaster rDNA. Cell. 1977 Feb;10(2):177–192. doi: 10.1016/0092-8674(77)90213-6. [DOI] [PubMed] [Google Scholar]